The only places I have read about pulling out "unconsciously" the bag are in forums, never in literature, and always with helium. They usually dont remember pulling off the bag, just wake up with the bag next to them. I dont believe they are lying, rather they use helium mixed with oxygen.
The sequence probably is as it follows. They lost conscious but keep alive because the O2 in the mix. They run out of helium/o2. Wake up because of co2 alarm. Pull off the bag desoriented. After some minutes they fully wake up, not knowing what happened.
The CO method is not dependent of how much oxygen is in the room but how much CO is generated with respect the size room. Hence the space must be isolated. At least you get a very high concentration of CO you will not lost conscious so fast, hence you can panick and open the doors.
In the inert gas method you lost your conscious suddenly and you will not wake up if the bag is still in place and the gas is still running. As a medical doctor, I am sure there is no such a thing as a "pull off bag" reflex. Not is mentioned such a thing in literature.
What do exists is convulsion and probably you will have it in any method but is in inert gas method that is REALLY relevant. Given you must operate the tank, the bag, AND bondage yourself the knot must be simple. There is no such a thing as a "untie knot" reflex either. Remember, you are unconscious and having a convulsion.
The goals must be (1) the chair doesnt fall, (2) you dont fall out the chair, (3) your arms never touch the bag , (4) your neck movement doesnt pull out the tube or loose the cord, (5) your head moving doesnt damage the bag with any surface (that is why you must be in a chair and not laying in bed) and (6) the tank is secured and dont fall.
The chair must be with no head support, no wheels, no spin, heavy enough so dont fall. You must be bondage in the torso so dont fall (you will lose your muscular tone like a doll and then get constractions). Constraining the wrists so they cant touch your face should be enough. Remember your head can fall, so recline and put some kitchen gloves so your nails cant scratch the bag.
I was thinking in a armchair or the copilot sea. Dont use the pilot seat as you can fall in the honk. Dont use a pc chair. Dont use a bed.
If you have read to this point you must be thinking there are much precautions to an already complex to assemble method. I think the same but they need to be done if you want to ctb sussesfully and not get severe brain damage.
It is a peacefully method? Absolutely. It is reliable, risk-free? No. It is possible to ctb even with no constraints at all but that is to leave too much to chance. Remember you are asphyxiating with a plastic bag and strange equipment, unconsciosly, all your body shaking. If the bag get damaged, the tube get off the bag or tank, you are done. If you can get N use that instead. If that is not possible, practice and take all the precautions you can.
As a personal note I am using just this method combined with phenobarbital (not N), so that would kill me if something with the inert gas go wrong.
